So far, I don't have a major vole problem, so my bulbs do fine in the ground. However, I would be a little concerned about moisture using plastic pots - either too much or too little, since the sides of the pot wouldn't let moisture in or out, so the only avenues for moisture to move would be the top or the holes in the bottom. I have also seen roots get slightly strangled in pot-bound plants I have purchased, as they grew out the holes. As well, the voles can dig down into the pots from the top, unless you cover the tops with wire. I would think wire cages would be better. While the price has gone up from what it used to be - and what hasn't!!?? - a roll of quarter-inch-mesh hardware cloth isn't exorbitant, and it will make a lot of cages that will allow for free water and root penetration. You could make a cardboard template, to get the size/shape to make 4 sides with top and bottom, and either use wire, or the j-hooks people use to make rabbit cages. Sorry, but I don't know a source for those, maybe your local farm supply store? Come to think of it, you might want to make the tops out of wide-mesh chicken wire, so the stems have room to grow up. And, it may be that tops aren't needed after all, since, as I said, I have no vole experience.

They more than likely have already re-seeded themselves and will pop up again the following spring. They are pretty easy to get started from seeds, too. Since yours is potted however, you can overwinter it indoors. If you want to bring it in, you can cut them back halfway or so, making sure to leave enough leaves for the plant to stay viable. Try to keep it on the humid side, by misting regularly and doing the trick of adding gravel, rocks, shards etc. to a planting tray and then set the pot on TOP of the gravel. The drainage water won't touch the soil and the water evap. will increase humidity quite a bit.

Charlotte, The best time to transplant them would be fall. Wait till the foliage will go brown and dry. The bed should have excellent drainage. You can divide the clump and plant bulbs at different places. In case that anything will go wrong at one of the locations, you will have a back up. I usually plant smaller bulbs with the large ones. Just remember that the depth of planting should be 2-3 times more than the bulb's diameter. Do not worry, Asiatics are tough! You can find more information here.

Lilies only bloom once per season. It is normal for the stems to brown and die. While the stems and leaves were green they were feeding the bulbs for next year. If you get a long enough period of cold weather in the winter your bulbs should bloom again next year just fine on their own schedule. These were probably forced for spring bloom. Lilies need a period of vernalization (cold treatment) to bloom the following year. I THINK it's about 6 weeks below 40 degrees, though I'm by no means positive. You may want to contact your local county extension office to find out if you have enough of a cold period for successfully growing lilies. Your extension agent or the local Master Gardeners should be able to help you.